Selenium supplements can slow the rise in virus levels in HIV-positive patients, which allows the number of beneficial CD4 immune cell to increase, according to results of a clinical trial supported by grants from the National Institutes of Health.

Low blood levels of selenium have been linked to high HIV virulence and more opportunistic infections, Dr. Barry E. Hurwitz and associates at the University of Miami in Florida report in the Archives of Internal Medicine. In lab experiments, the element suppresses HIV-1 replication.

Even when antiretroviral therapy (ART) is widely available, failure to keep the virus suppressed "is relatively common, due to the complexity and toxicity of the drugs," Hurwitz told Reuters Health. "Something like selenium is stable in the blood stream and may prevent 'viral escape'."

In their study, Hurwitz's team randomly assigned some 260 HIV-infected adults with no other major diagnosis to take 200-milligram capsules of inactive yeast (placebo) daily or 200-milligram capsules of high-selenium yeast. The researchers used selenium-enriched yeast (Selenomax, Nutrition 21 Inc.) because it contains high concentrations of organic, bioavailable forms of selenium.

After 9 months, viral load had increased by 10,000 to 20,000 copies/milliliter in the placebo group. Viral load was unchanged in the group on selenium supplementation, Hurwitz said, and CD4 cell counts increased.

The researchers identified 50 "selenium responders," whose blood levels of selenium rose significantly more than the average.

These responders tended to have greater adherence as determined by computerized electronic medication-monitoring caps compared with nonresponders, although some subjects with excellent compliance failed to absorb selenium.

Considering just the 50 selenium responders, their viral load actually decreased on average by 10,000 copies/milliliters, Hurwitz noted. Levels among nonresponders did not differ significantly from those in the plain yeast group.

The investigators conclude that selenium supplementation may represent "a simple, inexpensive, and safe adjunct therapy" to antiretroviral medications for HIV.

Hurwitz added that some stores sell the selenium-enriched yeast, with a 2-month supply costing about $15. However, consumers must be careful, he added, because many forms of selenium that are sold are not absorbed into the blood stream.

He also remarked on the potential impact that selenium supplementation could have in parts of world where soil is deficient in selenium, and people generally can't get enough from their food. "Selenium supplements could have very rapid and beneficial effects on HIV-infected individuals in those circumstances," he said.

SOURCE: Archives of Internal Medicine, January 22, 2007.

The hunt for a vaccine against AIDS is about to enter a critical stage, with results in 2008 from large-scale clinical trials of two candidates set to determine the future direction of research.

Although there is a good chance that neither experimental vaccine will provide comprehensive protection, Seth Berkley, head of the nonprofit International AIDS Vaccine Initiative, is optimistic scientists are on the road to developing a viable shot.

Even if today's vaccines reduce HIV infection rates by only a little, he is confident this would provide a springboard for more effective next-generation products.

HIV is uniquely difficult to vaccinate against, because the virus infects the very immune system cells that are usually stimulated by a vaccine.

Highest hopes are pinned on a vaccine from Merck & Co. Inc.. Expectations are lower for a rival product from Sanofi-Aventis and VaxGen Inc.

"Next year is a pretty important year," Berkley said in an interview ahead of the World Economic Forum in Davos.

"If we have an intermediate result, it is still very, very important, because it allows us to validate the animal models and really improve on it."

If the Merck vaccine does not work at all, then other approaches will have to be pursued.

The AIDS virus infects around 40 million people globally, most of them in sub-Saharan Africa. It killed an estimated 2.9 million in 2006, according to UNAIDS, the U.N. program on

HIV/AIDS.

The two vaccines now in advanced human testing work by producing cellular immunity, and Berkley said more effort was needed to research other approaches such as neutralizing antibodies.

Nonetheless, he is convinced strides are being made in the laboratory and in the growing number of clinical trials underway in both developed and developing countries.

"Do I think we are going to solve this at the end of the day? Absolutely," Berkley said.

"If you go back 10 years, it was as bleak as could be. Ten years later, we have a wide pipeline; we have multiple efficacy trials; everybody making vaccine is considering the needs of the developing world; there is political leadership and there has been a 500 percent increase in money."

A major U.S. AIDS treatment group plans to file a lawsuit on Monday that accuses drug giant Pfizer Inc. of illegally promoting recreational use of its blockbuster impotence pill Viagra.

The AIDS Healthcare Foundation (AHF) told Reuters it wants Pfizer to be barred from marketing Viagra as a lifestyle or sexual enhancement drug. The nonprofit organization said Pfizer's actions had led to risky behavior by men and an increase in HIV and other sexually transmitted diseases.

"Pfizer has created and contributed to the perception of Viagra as a safe, sexy, lifestyle, recreational drug, to be frequently used regardless of the degree, or even existence of" erectile dysfunction, the group said in draft legal documents.

Pfizer, the world's largest drug maker, said it was committed to appropriate Viagra use and urged men to see a doctor for a proper diagnosis. The drug is sold by prescription.

AHF, in its legal arguments, pointed to several Viagra promotions from recent years, including a 2005 newspaper ad that featured a smiling man asking, "What are you doing on New Year's Eve?"

Another ad that ran near the 2006 Super Bowl urged men to "Be this Sunday's MVP" and ask their doctors about Viagra.

Pfizer's Viagra Web site asks readers, "Want to improve your sex life?" and says the drug can help men who have erection difficulties "once in a while."

AHF President Michael Weinstein said the promotions made Viagra sound like a "party drug" that can make sex more pleasurable for healthy men -- a claim the U.S. Food and Drug Administration has not approved.

Men in the ads also look much younger than Pfizer's earlier Viagra pitchman, former Kansas Sen. Bob Dole, who is now 83, he said.

"Bob Dole has been replaced by the hunky 40-something guy who looks like he can really have a good time," Weinstein said in an interview. "The message they are sending out is that any and every male should take it," he added.

Studies show evidence of recreational Viagra use among men who have sex with men, sometimes to overcome the erection-inhibiting effects of alcohol or street drugs such as ecstasy and crystal methamphetamine, AHF said.

The group asked Pfizer repeatedly to alter its ads, Weinstein said.

In 2004, the FDA objected to a television commercial suggesting Viagra could return a man to the "wild thing" of his younger days. The FDA said the ad, showing a man sprouting devilish horns, made an unproven claim that men could regain a youthful level of sexual desire. Pfizer halted that campaign.

AHF's lawsuit, to be filed in Los Angeles Superior Court, asks that Pfizer be prohibited from running similar messages and ordered to fund awareness ads about sexually transmitted disease risks and Viagra.

The suit also requests that Pfizer turn over profits gained from misleading ads and pay AHF's costs of treating AIDS and other illnesses linked to Viagra use.

California-based AHF runs AIDS clinics in the United States, Africa, Latin America, the Caribbean and Asia that provide medical care and services to more than 53,000 people even if they cannot pay.

Pfizer spokeswoman Shreya Prudlo said the company was not aware of the planned lawsuit. She said Pfizer "has always been committed to safe and appropriate use of Viagra" and that the drug's label and promotions stated "Viagra does not protect against sexually transmitted diseases, including HIV."

Sales of Viagra, known generically as sildenafil, reached $1.6 billion worldwide in 2005.

Sales growth has been crimped by competition from rival impotence medicine Cialis, which is sold by a joint venture of Eli Lilly & Co. and Icos Corp.. Cialis works up to 36 hours, while Viagra works for about four hours.